As a general rule, either substantive dyes or oxidation dyes are used for coloring keratinic fibers. Although intense colors with good fastness properties may be obtained with oxidation dyes, the development of the color generally takes place under the influence of oxidizing agents such as H2O2 for example, which in some cases may result in damage to the fiber. Furthermore, some oxidation dye precursors or certain mixtures of oxidation dye precursors may have a sensitizing effect on people with sensitive skin.
For temporary colors, coloring or tinting agents are conventionally used which include substantive dyes as the coloring component. These are dye molecules which attach directly to the hair and require no oxidative process to develop the color. Substantive dyes are applied under gentler conditions. The disadvantage of these dyes, however, lies in the fact that the colors often have inadequate fastness properties, in particular with regard to hair washing, but also with respect to external influences, such as sunlight, or reactive environmental chemicals, such as swimming pool water, for example. Such colors are also generally significantly more sensitive to shampooing than oxidative colors, such that an often undesired shift in shade or even a visible decolorization then occurs very much more quickly.
Achieving a uniform coloring of hair that has been frequently treated, such as for example bleached or permanently waved hair, where the fiber presents differing degrees of pre-existing damage in the various lengths or variously treated areas, represents a particular challenge in terms of coloring hair with substantive dyes. During the coloring process itself, the coloring agent may exhibit an uneven coloring behavior on hair with differing degrees of pre-existing damage, while repeated hair washing may also cause the dyes to be washed out of the different areas of the hair to varying degrees, resulting in an inconsistent, and hence undesirable color result.
In the development of coloring products based on substantive dyes, there is therefore still a particular focus on producing dye formulations having reduced selectivity, meaning that a uniform color result may be achieved on sections of the hair that have varying degrees of pre-existing damage. In particular, this reduced selectivity should still be present not only immediately after the coloring process, but also after repeated hair washes.
An object of the present specification is therefore to provide a coloring agent for keratinic fibers, in particular human hair, which, in addition to other positive fastness properties, has in particular a low selectivity (or a good equalizing capacity) and good wash fastness.
The colors achieved with the agents according to the present specification should deliver a brilliant and intense color result, both immediately after the coloring process and after repeated hair washes. Following application of the coloring agent, the hair should be uniformly colored, even in cases where the hair exhibits varying degrees of pre-existing damage, wherein this uniformity in the color result should still be present even after repeated hair washes.
In the present specification, another object is to provide brilliant and neutral shades in the blue range with the aforementioned advantageous fastness properties, said shades being extremely suitable for matting. In addition, the application of the agents should increase the shine of the hair and prevent the scalp from drying out.
The use of cationic anthraquinone dyes in products for coloring keratinic fibers is already known in principle from the prior art, for example from EP 1 006 154 B1 or EP 1 820 826 A1. Furthermore, combinations of cationic anthraquinone dyes with oxidation dye precursors of the developer type are claimed in EP 2 329 809 for the oxidative coloring of hair.
Combinations of cationic anthraquinones with special fatty acid triglycerides have not yet been described.
During the course of the work leading to the agents of the present disclosure, it was surprisingly found that combinations of cationic anthraquinone dyes and special fatty acid triglycerides lead to colors which achieve the above object to an outstanding degree.
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with this background of the invention.